Swift: Type does not confirm to protocol 'BooleanType.Protocol'

Question

I'm getting an error when trying to check if an optional variable is set or not.

Error: Type CGPoint? does not confirm to protocol 'BooleanType.Protocol'

This is my code:

var point : CGPoint?

if (point) {
   ...
}

Isn't this how optional types in Swift are supposed to be used?

How should the if-comparison be written?

Answer 1

Since beta 5, you should write point == nil or point != nil .

This change was made because of confusion when the value was an optional boolean. For example:

let maybe : Bool? = false
if maybe {
    // executed because `maybe` is an optional having a value (false),
    // not because it is true
}

You can also use the conditional assignment as before:

if let assignedPoint = point { 
    /* assignedPoint is now a CGPoint unwrapped from the optional */ 
}